Excitation function of thermal freeze-out parameters and their correlations from strange hadrons spectra in Au–Au collision at 54.4 GeV

We present a systematic study of Gold–Gold (Au–Au) collision system at 54.4 GeV conducted by the STAR Collaboration at RHIC. The transverse momentum spectra of the strange hadrons, namely K_S⁰, Λ, Λ̄, Ξ̄⁺ and Ξ⁻ are studied at mid-rapidity |y|<0.5 for seven centrality classes. We applied the blast wave model with Tsallis statistics (TBW) with two flow profiles (n₀ = 1 and n₀ = 2) in order to compare the results and to check the sensitivity of n₀ to the freeze-out parameters. It is found that the TBW model with both the flow profiles can describe the particle spectra. In addition, the bulk properties in terms of kinetic freeze-out temperature (T₀), transverse flow velocity (β_T), the non-extensive parameter (q), the kinetic freeze-out volume (V), the mean transverse momentum (〈p_T〉), and the multiplicity parameter (N₀) are also extracted. All the parameters decrease with decreasing the event centrality, however, the non-extensive parameter q has the opposite behavior. There is an abrupt decrease seen in 0–5% to 30–40% centrality, while a slight decrease appears in 40–60% and 60–80% centrality in T₀, β_T, V, and 〈p_T〉. On the other hand, the parameter q follows the same scenario with an opposite trend with centrality. T₀ and 〈p_T〉 are larger for massive particles while β_T, q, V and N₀ are larger for lighter particles. The larger T₀ and 〈p_T〉, and smaller β_T, V, and q for the massive particles affirm that the heavy particles freeze-out early. Moreover, the multiple kinetic freeze-out and volume differential freeze-out scenarios are reported, as the former increase while the latter decrease with particle mass. In addition, T₀, q, V, and N₀ obtained from TBW model with n₀ = 1 are compatible to that of n₀ = 2. On the other hand, β_T is slightly larger in n₀ = 2, while 〈p_T〉 is slightly larger in n₀ = 1. Furthermore, we also reported some important correlations among the extracted parameters. Among these correlations, the positive correlation exist between T₀ and β_T, T₀ and V, T₀ and 〈p_T〉, T₀ and N₀, β_T and 〈p_T〉, β_T and V, β_T and N₀, V and N₀, and 〈p_T〉 and N₀, while the negative correlation of T₀ and q, and 〈p_T〉 and q.